1. Field of the Invention
The present invention relates to an image forming apparatus that employs an image forming portion to form an image on a printing medium that is conveyed by a conveying portion.
2. Description of the Related Art
At present, image forming apparatuses that can form images on various types of printing media have been developed, and have been used in various different fields. These image forming apparatuses are also very frequently employed as, for example, coupon printers or small commodity label printers, for limited applications. Therefore, for installing the image forming apparatus, not only a usual desktop area, but also a shelf or another location tends to be selected in accordance with the use.
Since various applications and the installation locations can be selected, the situation where there is a restriction on the space for installing the image forming apparatus has also occurred. For example, in a printing apparatus wherein the cover portion needs to be pivoted upward to clear a paper jam, a space for allowing the upward movement of the lid must be obtained. Further, in a case wherein a location where the image forming apparatus must be moved when sheets are to be loaded is selected, there is a restriction that space for moving the image forming apparatus should be obtained near the installation location.
There is a proposal for reducing the installation space, and according to this proposal, one part of the conveying part that conveys a printing medium to a discharge part is to be extracted in one direction (e.g., in a direction in which the printing medium is to be discharged), and the space required to perform a paper jam clearing process and a sheet setting process is limited only to the front of the apparatus. In Japanese Patent Laid-Open NO. 2010-18406, for example, an apparatus where a sheet cassette is to be pulled out in a paper discharge direction is disclosed.
However, in the arrangement wherein the sheet cassette and the conveying part are to be extracted in one specific direction, the accuracy for positioning the sheet cassette and the conveying part in the conveying direction can be easily obtained, but the positioning accuracy in the vertical direction is difficult. When the satisfactory vertical positioning accuracy is not obtained, there is a possibility that sheet feeding, conveying and image forming may not be appropriately performed. Especially, the vertical positioning accuracy is reduced for the conveying part, the position relative to the image forming unit is deviated, and this deviation greatly affects the image quality.